I have reproduced the issue using the grid plugins example. It looks like rowBodyTpl will not accept an XTemplate, only a (array of) raw string(s). Which is unexpected since the RowExpander calls Ext.XTemplate.getTpl which should allow for existing Templates according to the dos.

So after breaking down the Ext.Loader so I could set breakpoints I encountered this:// TODO: if XTemplate/Template receives a template as an arg, should// just return it back!

I think this was fixed in Ext 4.1.2 / 4.1.3 and therefore not mentioned anymore in the source you see when opening the docs. And that leads me to the conclusion that you are using Ext 4.1.1(a) ?

I have reproduced the issue using the grid plugins example. It looks like rowBodyTpl will not accept an XTemplate, only a (array of) raw string(s). Which is unexpected since the RowExpander calls Ext.XTemplate.getTpl which should allow for existing Templates according to the dos.

So after breaking down the Ext.Loader so I could set breakpoints I encountered this:// TODO: if XTemplate/Template receives a template as an arg, should// just return it back!

I think this was fixed in Ext 4.1.2 / 4.1.3 and therefore not mentioned anymore in the source you see when opening the docs. And that leads me to the conclusion that you are using Ext 4.1.1(a) ?

I had the same issue. Thank you, sir, for saving me time with such a great explanation!